21689882 has 4 divisors (see below), whose sum is σ = 32534826. Its totient is φ = 10844940.

The previous prime is 21689867. The next prime is 21689893. The reversal of 21689882 is 28898612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21631801 + 58081 = 4651^2 + 241^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5422469 + ... + 5422472.

Almost surely, 2^21689882 is an apocalyptic number.

21689882 is a deficient number, since it is larger than the sum of its proper divisors (10844944).

21689882 is a wasteful number, since it uses less digits than its factorization.

21689882 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10844943.

The product of its digits is 110592, while the sum is 44.

The square root of 21689882 is about 4657.2397404471. The cubic root of 21689882 is about 278.8810873718.

The spelling of 21689882 in words is "twenty-one million, six hundred eighty-nine thousand, eight hundred eighty-two".